Conventionally during TCS control in vehicular brake control systems, the non-driven wheels are not subject to the TCS control which generates braking force so brake fluid pressure is not applied to the wheel cylinders (hereinafter, simply referred to as “W/C” or “W/Cs”) of those wheels. More specifically, by closing pressure increase control valves (normally open valves) provided in a brake conduit which connects a master cylinder (hereinafter, simply referred to as “M/C”) to the W/Cs corresponding to the non-driven wheels, the brake fluid pressure is prevented from being applied to those W/Cs.
Further, by closing the pressure increase control valves provided in the brake conduits which connect the M/C to the W/Cs corresponding to the wheels for which the pressure is to be decreased or maintained, the brake fluid pressure applied to the W/Cs can be prevented from increasing when decreasing or maintaining the pressure, just as when the pressure is decreased or maintained during ABS control (see publication of Japanese Patent No. 2900542, for example).
Thus, the pressure increase control valves which control brake fluid pressure applied to the W/Cs of the non-driven wheels are closed during TCS control, and the pressure increase control valves which control brake fluid pressure applied to the W/Cs of the vehicle wheels for which the pressure is to be decreased or maintained are also closed when the pressure is to be decreased or maintained during ABS control. In order to close the pressure increase control valves at this time, a current value of the current flowing to the pressure increase control valves is set to a large value which enables the flow of brake fluid pressure to be reliably stopped by the pressure increase control valves, regardless of the brake fluid pressure upstream and downstream of the pressure increase control valves, e.g., regardless of the differential pressure between the pressure upstream of the pressure increase control valves and the pressure downstream of the pressure increase control valves.
Since the current value of the current flowing to the pressure increase control valves is primarily determined to be a large value, an unnecessary larger current is supplied to solenoid coils of the pressure increase control valves and an IC in an ECU which supplies the current that is supplied to the solenoid coils. Therefore, more electricity than is necessary is consumed. Accordingly, excess heat is generated by the solenoid coils and the IC in the ECU.